Include additional test cases

Author: porada

test-d/unwrap-partial.ts

@@ -74,9 +74,17 @@ type ArrayLikeTestType = {
 	[index: number]: string;
 };
 
+type PlainObjectTestType = {
+	readonly [key: string]: number | undefined;
+};
+
 expectType<ArrayLikeTestType>({} as UnwrapPartial<Partial<ArrayLikeTestType>>);
+expectType<PlainObjectTestType>({} as UnwrapPartial<PlainObjectTestType>);
 expectType<Record<number, string>>({} as UnwrapPartial<Partial<Record<number, string>>>);
 expectType<string[]>({} as UnwrapPartial<Partial<string[]>>);
+expectType<Array<string | undefined>>({} as UnwrapPartial<Array<string | undefined>>);
+expectNever({} as UnwrapPartial<string[]>);
+expectNever({} as UnwrapPartial<{[p: string]: number}>);
 
 // `UnwrapPartial` works with tuples
 type TestTuple = [string, number, boolean];